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Hi, can you help to find (all the roots/zeros), please!!!

Hi, can you help to find (all the roots/zeros), please!!!-example-1
User Davor Mlinaric
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1 Answer

30 votes
30 votes

Solution:

Given a quadratic equation;


ax^2+bx+c=0

The roots x of the equation is;


x=\frac{-b\pm\sqrt[]{b^2-4ac}}{2a}

Given;


x^2-2x-12=0
a=1,b=-2,c=-12

The values of x are;


\begin{gathered} x=\frac{-(-2)\pm\sqrt[]{(-2)^2-4(1)(-12)}}{2(1)} \\ x=\frac{2\pm\sqrt[]{4+48}}{2(1)} \\ x=\frac{2\pm\sqrt[]{52}}{2} \\ x=\frac{2\pm2\sqrt[]{13}}{2} \\ x=1\pm\sqrt[]{13} \end{gathered}

Then, we can separate the solution;


x=1+\sqrt[]{13},x=1-\sqrt[]{13}

Hence, the roots of the quadratic equation are;


\begin{gathered} x=1+\sqrt[]{13} \\ x=1-\sqrt[]{13} \end{gathered}

User UnitStack
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